Metamaterial is a novel kind of material, which consists of based material, and a number of artificial microstructures attached on the surface of the based material or embedded in the interior of the based material. The artificial microstructure is made up by cylindrical or flat wires forming predetermined geometric figure, such as circular ring, “I” shaped wires, and the like. The based material act as support to the artificial microstructures. The based material can be any material that is different from the material of artificial microstructures. Combination of the two kinds of materials can develop an equivalent dielectric constant and permeability in space. The equivalent dielectric constant and equivalent permeability of each point in the metamaterial can be designed by designing the shape and arrangement of each artificial microstructure in the metamaterial.
When an electromagnetic wave beam is propagating from one medium to another medium, the electromagnetic wave will be refracted. When the refractive indices distribution of the material is heterogeneous, the electromagnetic wave will deflect towards locations with relatively large refractive indices. The refractive indices of electromagnetic wave is directly proportional to √{square root over (∈×μ)}. Therefore, by changing the distribution of dielectric constant ∈ and/or permeability μ material, the purpose of changing the propagation path of electromagnetic wave can be achieved.
In prior art, the deflection of the electromagnetic waves is achieved by changing the direction of the electromagnetic waves by means of mechanical adjustment. However, the deflection of the electromagnetic waves by means of mechanical adjustment is not flexible enough, and the adjustment is not convenient.